Technical 88 carbed 999cc FIRE not pulling fuel

[a73uk]

Has anyone had an issue on a FIRE engine with either camshaft wear, or pump rod worn, to the point it wont pull fuel?
The car was filled (with E5), got home, but then wouldnt re-start a week or 2 after. There was no fuel getting to the filter. Runs with a cheapo Chinese electric pump. Changed the fuel pump (with a new, genuine Fiat one), still wouldnt pull fuel.. Completely drained the tank, lifted the back seat, pulled the sender out, the pickup pipes weren't restricted, blew the feed & return lines out (weren't blocked), a couple of small pieces of black ABS plastic chunks in the tank (which wouldn't have got past the sender base filter), no significant dirt in the tank... Now I`m stuck..

All I can think of is either a worn pump actuation rod, or, a severely worn cam? Its only done 46,000 miles though.. I mean, there's nothing else in the system really! Anyone had anything like this?

If I cant sort it out, I`m gonna have to fit an electric pump, which I don't really want to do, as it`ll detract from the originality, plus, there's not many places it can fit, without cutting the rigid plastic fuel lines..

 

[ZaphodB]

won't pull fuel

You mean push fuel surely......

The pump will push fuel to the reservoir in the carb, rest of the 'distribution' is done by the carb

Explain further what's occurring

 

[bugsymike]

Has anyone had an issue on a FIRE engine with either camshaft wear, or pump rod worn, to the point it wont pull fuel?
The car was filled (with E5), got home, but then wouldnt re-start a week or 2 after. There was no fuel getting to the filter. Runs with a cheapo Chinese electric pump. Changed the fuel pump (with a new, genuine Fiat one), still wouldnt pull fuel.. Completely drained the tank, lifted the back seat, pulled the sender out, the pickup pipes weren't restricted, blew the feed & return lines out (weren't blocked), a couple of small pieces of black ABS plastic chunks in the tank (which wouldn't have got past the sender base filter), no significant dirt in the tank... Now I`m stuck..

All I can think of is either a worn pump actuation rod, or, a severely worn cam? Its only done 46,000 miles though.. I mean, there's nothing else in the system really! Anyone had anything like this?

If I cant sort it out, I`m gonna have to fit an electric pump, which I don't really want to do, as it`ll detract from the originality, plus, there's not many places it can fit, without cutting the rigid plastic fuel lines..

Are you talking about a mechanically actuated lift pump running from the engine camshaft?
Generally speaking if they have been running and then when left for a few days the diaphragm has failed.
In the old days we often had to replace pump diaphragms, the two valves inside the pumps much less so , often just a case of cleaning dirt out so the flap valve would seat better.
Modern replacement lift pumps of dubious quality often do not engage with the cam correctly either through fitter error or poor manufacturing.
If it is possible to dismount the poump from engine but keep the inlet pipe on, can you work the actuating arm to test it as usually a few strokes and petrol will be squirting out.
If you are talking about something like this below , then the actuating rod length will affect operation, so wear in engine rod or at cam will affect things also if too thick a gasket has been fitted bringing pump away from the actuating rod.
All of these things can be tested.
First I would do as I suggested and work the actuator on the pump while inlet connected and pump away from engine mounting point and it should pump fuel out, if not and pipe to tank is clear then replace pump.
If it works off car then inspect rod operation.
It may be possible with care to push rod into place and gently hold your finger against it to see when engine cranking if rod moves in and out, if it doesn't then cam lobe issue, if it does then maybe length of actuating rod issue.
If that is the case , do not simple fit a longer rod as it may push to far and destroy the pump.

 

[a73uk]

You mean push fuel surely......

The pump will push fuel to the reservoir in the carb, rest of the 'distribution' is done by the carb

Explain further what's occurring

Well, it has to pull the petrol from the tank first, then it sends to to the carb.

As I said, its not able to get fuel from the tank to the filter or pump.

Are you talking about a mechanically actuated lift pump running from the engine camshaft?
Generally speaking if they have been running and then when left for a few days the diaphragm has failed.
In the old days we often had to replace pump diaphragms, the two valves inside the pumps much less so , often just a case of cleaning dirt out so the flap valve would seat better.
Modern replacement lift pumps of dubious quality often do not engage with the cam correctly either through fitter error or poor manufacturing.
If it is possible to dismount the poump from engine but keep the inlet pipe on, can you work the actuating arm to test it as usually a few strokes and petrol will be squirting out.
If you are talking about something like this below , then the actuating rod length will affect operation, so wear in engine rod or at cam will affect things also if too thick a gasket has been fitted bringing pump away from the actuating rod.
All of these things can be tested.
First I would do as I suggested and work the actuator on the pump while inlet connected and pump away from engine mounting point and it should pump fuel out, if not and pipe to tank is clear then replace pump.
If it works off car then inspect rod operation.
It may be possible with care to push rod into place and gently hold your finger against it to see when engine cranking if rod moves in and out, if it doesn't then cam lobe issue, if it does then maybe length of actuating rod issue.
If that is the case , do not simple fit a longer rod as it may push to far and destroy the pump.

It is a mechanical pump, on an 88 carbed Panda. When I initially saw it wasn't pulling fuel by itself, but was able to with an additional electric pump put in series (between the filter & mechanical pump) I thought, ok, needs a new pump (even though I`ve had dozens of Fiats with the same carb fed FIRE engines & never needed to replace the pump on a single one, even at 170,000+ miles), so, as I said, I ordered a brand new, genuine Fiat original (7581032) from Italy, as I don't trust aftermarket pumps either, & here we are, still no pumping with a new pump..

I did try to actuate the old one when it was still fitted, far from easy, as the lever/pad that the rod actuates is very small (maybe 5mm square) & recessed about 1 cm deep inside the pumps body), plus, it has a strong spring behind it, so trying to actuate it while holding it in your hand, still connected to the lines, is almost impossible. I didn't have anyone to turn the key, so I couldn't check the amount of rod movement, it had already occurred to me. Hopefully I will have someone with me next time I go to it, so I can feel how much throw its got, & compare it to one of my Uno`s.

The spacer wasn't touched, it stayed on the head when I took the old pump off & I left it there when I put the identical replacement on, so that shouldn't be a issue.

Its very odd, that it was running absolutely fine, no starting issues, no sign of fuel starvation when driving, even at motorway speeds, ever, & then all of a sudden, no fuel.. I mean, it doesn't make sense that either the cam lobe or pump rod would suddenly "wear out" either, but, I`m all out of ideas, having literally checked everything else.. Its hardly a complicated setup..

Oh, its worth pointing out, I checked the timing belt, in case it had snapped, & took the cam cover off, to check the pulley was still attached, & took the dizzy cap off to check the rotor arms turning, & the cams rotating perfectly well, + there's no wear showing on the rest of the cam lobes.

 

[bugsymike]

Well, it has to pull the petrol from the tank first, then it sends to to the carb.

As I said, its not able to get fuel from the tank to the filter or pump.


It is a mechanical pump, on an 88 carbed Panda. When I initially saw it wasn't pulling fuel by itself, but was able to with an additional electric pump put in series (between the filter & mechanical pump) I thought, ok, needs a new pump (even though I`ve had dozens of Fiats with the same carb fed FIRE engines & never needed to replace the pump on a single one, even at 170,000+ miles), so, as I said, I ordered a brand new, genuine Fiat original (7581032) from Italy, as I don't trust aftermarket pumps either, & here we are, still no pumping with a new pump..

I did try to actuate the old one when it was still fitted, far from easy, as the lever/pad that the rod actuates is very small (maybe 5mm square) & recessed about 1 cm deep inside the pumps body), plus, it has a strong spring behind it, so trying to actuate it while holding it in your hand, still connected to the lines, is almost impossible. I didn't have anyone to turn the key, so I couldn't check the amount of rod movement, it had already occurred to me. Hopefully I will have someone with me next time I go to it, so I can feel how much throw its got, & compare it to one of my Uno`s.

The spacer wasn't touched, it stayed on the head when I took the old pump off & I left it there when I put the identical replacement on, so that shouldn't be a issue.

Its very odd, that it was running absolutely fine, no starting issues, no sign of fuel starvation when driving, even at motorway speeds, ever, & then all of a sudden, no fuel.. I mean, it doesn't make sense that either the cam lobe or pump rod would suddenly "wear out", but, I`m all out of ideas, having literally checked everything else.. Its hardly a complicated setup..

Oh, its worth pointing out, I checked the timing belt, in case it had snapped, & took the cam cover off, to check the pulley was still attached, & took the dizzy cap off to check the rotor arms turning, & the cams rotating perfectly well, + there's no wear showing on the rest of the cam lobes.

You are certainly checking all the right things.
I agree those pumps are hard to activate due to no lever as such , but if you have a short socket extension bar from memory, I was able to activate them.
I used to test them in my parts cleaning tank with a length of hose.
You only need the inlet hose on to see if pump trying to operate.
You are happy no blockage in fuel line from tank?

 

[ZaphodB]

I tried searching for pictures of the camshaft for this engine (which I believe is 5970312) , there's very few, but a couple of pics show the main camshaft (with 8 lobes) and a much shorter shaft with one lobe , maybe the drive to this shorter shaft is broken/disconnected?

I can't see many pics of the arrangement

 

[bugsymike]

I tried searching for pictures of the camshaft for this engine (which I believe is 5970312) , there's very few, but a couple of pics show the main camshaft (with 8 lobes) and a much shorter shaft with one lobe , maybe the drive to this shorter shaft is broken/disconnected?

I can't see many pics of the arrangement

I may be wrong but I think that would be the earlier pushrod 903cc? engine with the fuel pump mounted low on the engine block possible driven by a gear driven camshaft.
I think OPs is the engine after that, but the very early Fire 999cc? before injection so as still carb, had the fuel pump driven by a pushrod from the normal camshaft in the cylinder head, so pump mounted on side of head?
Of course I stand to be corrected.

 

[ZaphodB]

Me too

Just by chance I've just found another diagram , which shows a lone cam .,,,...,

Item 5 https://eper.fiatforum.com/en/Drawings/Detail/F/F/GIN/LV/102/2/1/0/SubSubGroup

But again no indication where that fits to , but I do see a off centre smaller hole , maybe there's a pin there to lock it to whatever drives it (and it's broken)

Or maybe item 6 (bush) is missing ?

If it is the right diagram of course

To the OP , if you put your VIN into ePER it'll narrow down what's on your vehicle.

 

[Mike1alike]

blew the feed & return lines out (weren't blocked)

Not blocked is good but also check them for cracks/holes.

 

[a73uk]

You are certainly checking all the right things.
I agree those pumps are hard to activate due to no lever as such , but if you have a short socket extension bar from memory, I was able to activate them.
I used to test them in my parts cleaning tank with a length of hose.
You only need the inlet hose on to see if pump trying to operate.
You are happy no blockage in fuel line from tank?

Maybe if I take the spacer out, put the fuel pump back onto the studs (4-5 turns of the nuts), then maybe it`ll give me enough room to put a 1/4" extension or wide flathead in the gap to actuate the pad on the pump.. I`ll check next time I go (I`m working on someones driveway miles away, which makes things difficult).

As I said, I checked both the feed & return lines, in both directions, neither appeared blocked, & it starts & runs fine on the crappy Chinese electric pump.

Me too

Just by chance I've just found another diagram , which shows a lone cam .,,,...,

Item 5 https://eper.fiatforum.com/en/Drawings/Detail/F/F/GIN/LV/102/2/1/0/SubSubGroup

But again no indication where that fits to , but I do see a off centre smaller hole , maybe there's a pin there to lock it to whatever drives it (and it's broken)

Or maybe item 6 (bush) is missing ?

If it is the right diagram of course

To the OP , if you put your VIN into ePER it'll narrow down what's on your vehicle.

Thats not a FIRE setup, probably 903cc, although it works very similarly. You cant actually see the pump lobe on the FIRE, as its inside the end cam-cap, like this:

 

[ZaphodB]

OK

Maybe remove the pump, see if you can hand turn the engine (at the crank with a socket) and find a way of confirming the pump lobe is turning and lobing.

 

[a73uk]

To the OP , if you put your VIN into ePER it'll narrow down what's on your vehicle.

Eper doesn't recognise the VIN (I don't think it works on pre-1993-ish cars)

 

[ZaphodB]

Eper doesn't recognise the VIN (I don't think it works on pre-1993-ish cars)

If you use the model drop down list on https://eper.fiatforum.com/, it shows Panda's going back to 1985 so that's a bit weird, maybe navigate via that.

Or maybe ePER is incomplete , I dunno.

 

[a73uk]

Not blocked is good but also check them for cracks/holes.

The rubber sections at either end are fine, no cracking, seem to still be completely attached to the rigid nylon lines. There were no signs of leaks while it was running on the electric pump (for around 10 minutes).

OK

Maybe remove the pump, see if you can hand turn the engine (at the crank with a socket) and find a way of confirming the pump lobe is turning and lobing.

No, as I said earlier, I took the cam cover off & turned it over from the ignition, the cam rotates fine. Unfortunately its too far to reach/feel the rod while turning the ignition switch at the same time, so I need someone with me next time I go.

 

[ZaphodB]

No, as I said earlier, I took the cam cover off & turned it over from the ignition, the cam rotates fine. Unfortunately its too far to reach/feel the rod while turning the ignition switch at the same time, so I need someone with me next time I go.

Sorry missed that

But is that pump lobe actually part of the main camshaft or a separate part attached? , that is the question

 

[a73uk]

If you use the model drop down list on https://eper.fiatforum.com/, it shows Panda's going back to 1985 so that's a bit weird, maybe navigate via that.

Or maybe ePER is incomplete , I dunno.

That is weird, neither of the Panda`s VINs work on Eper (88 & 89), neither does my Mk1 Uno (89). Cant remember if my other Mk2 Uno`s work or not)

 

[a73uk]

Sorry missed that

But is that pump lobe actually part of the main camshaft or a separate part attached? , that is the question

The pump lobe is part of the cam on the FIRE, you don't have a floating lobe in there.

 

[bugsymike]

Maybe if I take the spacer out, put the fuel pump back onto the studs (4-5 turns of the nuts), then maybe it`ll give me enough room to put a 1/4" extension or wide flathead in the gap to actuate the pad on the pump.. I`ll check next time I go (I`m working on someones driveway miles away, which makes things difficult).

As I said, I checked both the feed & return lines, in both directions, neither appeared blocked, & it starts & runs fine on the crappy Chinese electric pump.



Thats not a FIRE setup, probably 903cc, although it works very similarly. You cant actually see the pump lobe on the FIRE, as its inside the end cam-cap, like this:

How about leaving pipes on , but pump away from mounting and place a M8 bolt or similar with the thread end pushing against the pumps actuator and put the other end/head of bolt against the engine casting , that way when you push against the pump the actuator arm will be worked, this will test the pump.
You will still need to see if rod is moving enough in the engine.

 

[ZaphodB]

Maybe you should just slap an electric pump in the car and be done with the mechanical one

 

[a73uk]

Sorry missed that

But is that pump lobe actually part of the main camshaft or a separate part attached? , that is the question

This is the FIRE setup, the "disc" on the right hand end of the cam is the fuel pump lobe, next to the distributor drive at the very end (thats all hidden under the last cam-cap):

10107/00 - DISTRIBUTION

FIAT PANDA 4X2 RL/86(1985-1991)

eper.fiatforum.com

How about leaving pipes on , but pump away from mounting and place a M8 bolt or similar with the thread end pushing against the pumps actuator and put the other end/head of bolt against the engine casting , that way when you push against the pump the actuator arm will be worked, this will test the pump.
You will still need to see if rod is moving enough in the engine.

Yeah, I`ll check the rod first, & compare it to my Uno (which is parked next to the Panda). If its got the same throw, I`ll try to actuate the pump manually again. I just need to have someone with me to turn the key while I check!